Wavy and fluted coulters for use in agricultural tillage implements are well known. For example, U.S. Pat. No. 5,649,602 to Bruce shows a wavy coulter that is made by cutting out a circular piece from a thick but flat piece of sheet metal, sharpening the outer peripheral edge thereof, using dies to deform the radially outer portion thereof to a particular wavy shape and then heat treating the blade to harden it so it will stay sharp and not become dull prematurely.
U.S. Published Pat. Application No. 2011/0240319 to Sanderson shows a fluted, scalloped and therefore wavy blade with an outer peripheral edge sharpened edge. A similar tillage blade is marketed under the trademark EXCALIBUR® and used on an Excelerator® Vertical Tillage System from Kuhn Krause. Looking at the photographs of this EXCALIBUR® blade makes it appear that the sharpened edge lies in a single plane, which single plane appears to be a vertical plane perpendicular to the axis of rotation thereof when the EXCALIBUR® blade is installed onto an Excelerator® Vertical Tillage System from Kuhn Krause.
A problem with some prior art wavy tillage blades of the aforementioned type is keeping them sharp after extended usage.
Accordingly, there is a need for a wavy coulters and discs that will efficiently cut through trash above the top of the soil and stay sharper longer than prior art wavy coulters.